Welding rod and the like



Patented May 4, 1937 T orFicE 2,079,482 WELDING ROD THE E No Drawing. Application September 23, 1935, Serial No. 41,782

12 Claims.

My invention relates to welding rods for use in forming bearings and bearing surfaces, and particularly but not exclusively to building up and reconditioning the bearing surfaces of locomotives and other machine parts.

Anexcellent bearing material consists predominantly of copper containing from 2 to 20% lead and from 1 to 20% tin, with the sum of the lead and tin between approximately 4 and 40%. An excellent example of such a bearing metal is 80% copper, 10% lead, and 10% tin.

Applicant has found that an improved dispersion of the lead in the above described bearing metal may be secured by arc-depositing the metals of the bearing from a source of metals in which the tin and lead are not alloyed with the copper. Preferably, the carbon-arc process is employed for this purpose, although the metallicarc process may be employed. In this connection it will be understood that the bearing and machining properties of the metal are much improved by a proper dispersion of the lead.

A convenient Way of performing the process is by use of a copper rod coated in any suitable way with tin and lead, preferably in the form of a tin-lead alloy, the amounts of these three metals being proportioned in the rod to give the desired composition of the bearing metal.

The above described rod may be coated either by dipping it in or spraying it with molten tinlead alloy or by wrapping it with a tape of tinlead alloy or separate tapes of tin or lead. Preferably, however, it is coated by drawing or extruding a tube of tin-lead alloy over it. Likewise this coating operation may be performed by dipping the rod into molten tin and then into molten lead, or part of the tin may be contained in the lead if the rod is first dipped in the lead, the lead preferably containing sufiicient tin, say 1 to 5% with relation to the lead, to make it adhere to the copper rod in the absence of said rod being first coated with tin or a tin-lead alloy. This coating may be placed on the rod in still .other ways, as electro-depositing successive layers of tin and lead thereon, and, in general, the composite rod may be formed in any of the ways of making such rods known to those skilled in the art.

The copper body of the rod may be either copper or copper containing a deoxidizer such as 0.005 to 0.25% phosphorus, or 0.05 to 0.5% silicon. Likewise, if desired, all or part of the tin may be alloyed with the copper, but if the body of the rod is to be produced by hot working the amount of tin therein should not exceed approximatey The above described bearing metal is not hot workable, and heretofore it and the stock therefor have been produced by expensive casting 5 methods. The above described process, besides producing an improved bearing metal in respect to securing an improved dispersion of the lead, has the decided economic advantage of enabling the employment of stock in the form of welding 10 rods which can be fabricated by hot working processes.

Phosphor-bronze gives particularly satisfactory results, and may be employed in the form of either a binary alloy or one containing tin. The alloys may contain 0.005 to 10 or 12% phosphorus, but not more than about 0.5% if they are to be worked cold, or more than about 0.1 to 0.25% if they are to be worked both hot and cold. The alloys may contain 0.1 to tin with or 20 without phosphorus, but they should not have more than about 15% tin if they are to bi. worked cold or more than about 5% tin if they are to be worked both hot and cold. A suitable rod having this type of alloy may consist of a hot workable body consisting of copper with up to 0.1% phosphorus coated with tin-lead alloy, say with 25% with relation to the copper of 50:50 solder to produce the above described bearing metal having 10% each of lead and tin, this coating preferably being formed by placing a tube of the tinlead alloy over the phosphor-bronze rod and then drawing the tube to make. it closely fit the rod.

During deposition of the rod the lead is finely divided by the arc. Phosphorus acts to prevent oxidization of the lead and thus to prevent destruction of the same, particularly more finely divided particles. In itself and by eliminating lead oxides it secures an improved bearing metal.

It has been found that the metal of the rods above described when deposited on ferrous parts, such as steel, do not readily bond with the same on account of the presence of high amounts of lead. Somewhere about 5% lead seems to be the maximum amount that may be present if a satisfactory bond is to be secured. With higher amounts of lead, to insure securing a bond with ferrous parts, and, if desired, with lesser amounts of lead, to produce a better bond, the ferrous part is preferably first treated by depositing thereon a copper-base metal which bonds readii to the ferrous material. Then the welding rod having tin and lead is deposited on this preliminary layer, the metal of such rod readily bonding with copper-base alloys.

Any of the usual copper-base welding rods which will bond with steel may be employed for depositing a layer on the ferrous part to be built up, prior to depositing the leaded welding rod. Such copper-base welding rods, for example, may consist of copper with a small percentage of silicon or may be a 96% copper, 3.5% silicon, 0.5% tin alloy or the like known to those skilled in the art. Preferably, this non-leaded welding rod is deposited by using the welding rodas an electrode, that is to say, by use of the metallic-arc process, while, as above described, upon this preliminary layer is then superimposed the bearing metal preferably by means of a carbon-arc, it being found that the carbon-arc, particularly, acts to disperse the lead very finely and uniformly throughout the mass of the deposit. I

It will be understood that wide deviations may be made from the invention described herein without departing from the spirit of the invention.

I claim:

1. A composite welding rod formed of a plurality of elements in definite juxtaposed substantially segregated relation selected from among copper, copper-base alloy containing tin, tin free copper-base alloy, tin, lead, and alloy contain ing tin and lead to form a welding rod presenting, approximately, 2 to 20% lead and 1 to 20% tin with the sum of the tin and lead between 4 and 40% and the balance predominantly copper, the rod linearly thereof having a substantially uniform metallic composition in respect to copper, tin and lead, which rod when arc-deposited will form a copper-base alloy weld metal containing tin and finely dispersed lead or lead-tin alloy.

2. A welding rod according to claim 1 presenting roughly about 10% eachof tin and lead.

3.. A welding rod according to claim 1 in which the lead presented is contained in a coating on an element which is at least largely copper.

4. A welding rod comprising a copperor copper-base alloy body provided with a coating containing tin and lead or lead-tin alloy, said rod presenting, approximately, 2 to 20% lead and 1 to 20% tin with the sum of the tin and lead between 4 and 40% and the balance predominantly copper, which rod when arc-deposited will form a copper-base alloy weld metal containing tin and finely dispersed lead or lead-tin alloy.

5. A welding rod according to claim 4 in which the coating is lead-tin alloy.

6. A welding rod according to claim 1 in which combined with the copper or copper-base alloy is a deoxidizer for lead.

7. A welding rod according to claim 4 in which said body is copper containing 0.005 to 12% phosphorus and the coating is lead-tin alloy.

8. A welding rod according to claim 4 in which said body is copper containing 0.005 to 0.5% phosphorus and the coating is lead-tin alloy.

9. A welding rod according to claim 4 in which said body is copper containing 0.005 to 0.1% phosphorus and the coating is lead-tin alloy.

, 10. A welding rod comprising a copper body containing 0.005 to 12% phosphorus coated with :50 lead-tin solder to present a rod having roughly about 10% each of tin and lead.

11. A welding rod according to claim 10 in which the phosphorus does not exceed 0.5%.

12. A welding rod according to claim 10 in which the phosphorus does not exceed 0.1%.

IRVING T. BENNETT. 

